The present invention relates to acousto-optic devices and a method of making one. More particularly, the invention provides for such a device which has an associated transducer bonded integrally with it.
Acousto-optic devices usually comprise an electrically driven piezoelectric transducer bonded to an acousto-optic medium. The medium material generally applied is a high refractive index material, such as telluride glass. Such devices have applications as light deflectors in optical memories, acoustic delay lines, acoustic switches, and light modulators. An acoustic strain wave provided by the transducer modulates the refractive index of the medium which in turn diffracts light in a preferred direction when light incident on the medium is near the Bragg angle. The medium acts as a grating, the grating period being equal to the wavelength of the sound in the medium.
Since the amount of sound which enters the acousto-optic medium depends on the quality of the bond between the transducer and the acousto-optic medium, the bond is important. U.S. Pat. No. 3,798,746 to Alphonse, issued Mar. 26, 1974, teaches that the bond between the transducer and the acousto-optic medium can be improved by following certain process steps and utilizing special metals as primer metals.
It is an object of the present invention to provide a natural bond between an acousto-optic medium and its associated transducer.
It is yet another object of the present invention to provide an acousto-optic device which has as the interaction material an injection moulded plastic with a transducer integrally bonded to it.
Other objects of the invention will be evident from the description hereinafter presented.